Device system and method for blood sample collection

ABSTRACT

A blood collection assembly to facilitate the assay of a blood sample, comprising: (i) an absorptive media configured to collect and release the blood sample, (ii) a cartridge defining a cavity and a blood-sampling end configured to hold the absorptive media against a dermal membrane containing the blood sample; (iii) a lancet disposed within the cavity and having a lance at one end thereof; and (iv) a plunger configured to extend and retract the lancet through the absorptive media to lance the dermal membrane and collect the blood sample within the absorptive media. The cartridge containing the blood-filled, absorptive media is configured to be placed into a blood assay device for extraction of the blood sample from the absorptive media.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Non-Provisional Utility Patent application whichclaims priority from a first U.S. Provisional Patent Application Ser.No. 62/322,840, filed Apr. 15, 2016 entitled “Blood Sample Device” andU.S. Provisional Patent Application Ser. No. 62/322,843, filed Apr. 15,2016 entitled “Food Sample Device.” The contents of the aforementionedapplications are hereby incorporated by reference in their entirety.

This application relates to U.S. patent application Ser. No. 15/157,584filed May 18, 2016 entitled “Method and System for Sample Preparation”which is a continuation of U.S. Non-Provisional patent application Ser.No. 14/056,603, filed Oct. 17, 2013, now U.S. Pat. No. 9,347,086, whichclaims priority to U.S. Provisional Patent Application Ser. No.61/715,003, filed Oct. 17, 2012, which is a continuation-in-part of U.S.patent application Ser. No. 12/785,864, filed May 23, 2010, now U.S.Pat. No. 8,663,918, which claims priority to U.S. Provisional PatentApplication Ser. No. 61/180,494, filed May 22, 2009, and which is also acontinuation-in-part of U.S. patent application Ser. No. 12/754,205,filed Apr. 5, 2010, now U.S. Pat. No. 8,716,006, which claims priorityto U.S. Provisional Patent Application Ser. No. 61/166,519, filed Apr.3, 2009. The contents of the aforementioned applications are herebyincorporated by reference in their entirety.

TECHNICAL FIELD

This invention relates to a device, system, and method for analyzingbiological samples. In one embodiment, a device, system and method forcollecting samples is disclosed for use in combination withmulti-chambered disposable cartridges for use in assaying blood samples.In another embodiment, a system and method is disclosed for use incombination with multi-chambered disposable cartridges for use inassaying food samples.

BACKGROUND

There is continuing interest to improve testing methodologies,facilitate collection and decrease the time associated with clinicallaboratories. Particular testing requires that a sample be disrupted toextract nucleic acid molecules such as DNA or RNA.

The number of diagnostic tests performed annually has increasedexponentially in the past decade. The use of molecular diagnostics andgene sequencing in research and medical diagnostics is also rapidlygrowing. For example, DNA testing has also exploded in view of thegrowing interest in establishing and tracking the medical history and/orancestry of a family. Many, if not all of these assays, could benefitfrom a rapid sample preparation process that is easy to use, requires nooperator intervention, is cost effective and is sensitive to a smallsample size.

Sample collection and preparation is a major cost component ofconducting real-time Polymerase Chain Reaction (PCR), gene sequencingand hybridization testing. In addition to cost, delays can lead to thespread of infectious diseases, where time is a critical component to itscontainment/abatement. In addition to delaying the test results, suchactivities divert much-needed skilled resources from the laboratory tothe lower-skilled activities associated with proper collection, storageand delivery.

For example, a portable molecular diagnostic system could be operated byminimally trained personnel (such as described in US 2014/0099646 A1)and have value with regard to disease surveillance. However, theadoption of such portable systems can be limited/constrained by currentmethods of sample collection, which require trained personnel to permitsafe and effective handling of blood and/or food samples for analysis.

A need, therefore, exists for an improved device, system and method forcollection, preparation and testing of fluid samples, facilitates theuse of minimally-trained personnel, facilitates the testing of bothblood and food samples, and may be used in combination with a portablemolecular diagnostic system.

SUMMARY

The present disclosure relates to a sample collection/carrier device andmethod for using the same when assaying fluid samples, such as blood andfood samples.

In one embodiment, a blood collection assembly is provided to facilitatethe assay of a blood sample, comprising: (i) an absorptive mediaconfigured to collect and release the blood sample, (ii) a cartridgedefining a cavity and a blood-sampling end configured to hold theabsorptive media against a dermal membrane containing the blood sample,(iii) a lancet disposed within the cavity and having a lance at one endthereof, and (iv) a plunger configured to extend and retract the lancetthrough the absorptive media to lance the dermal membrane and collectthe blood sample within the absorptive media. The cartridge containingthe blood-filled, absorptive media is configured to be placed into ablood assay device for extraction or elution of the blood sample fromthe absorptive media.

In another embodiment, a device is provided to facilitate the assay of afluid sample, comprising: (i) an absorptive media configured to collectand release the fluid sample, and (ii) a carrier configured to: (a) holdthe absorptive media in contact with the fluid sample during collection,(b) carry the absorptive media into an apparatus for assaying the fluidsample, and (c) produce a fluid-retaining barrier with the apparatuswhile assaying the fluid sample.

In another embodiment, a dual-barrel syringe is provided to facilitatethe preparation of a diagnostic fluid sample, comprising: (i) a firstsyringe operative to draw a quantity of the fluid sample, (ii) a secondsyringe containing a lysis buffer, the first and second syringesdefining first and second barrels, respectively, which are juxtaposedand share a common wall, and (iii) a valve mechanism containing a nozzlewhich may be rotated into in fluid communication with an opening in eachof the first and second barrels.

In yet another embodiment, a food assay system is provided to facilitatethe assay of a fluid sample, comprising: an absorptive media configuredto collect and release the fluid sample, and a disposable assaycartridge configured to assay the fluid sample for detecting thepresence of a select attribute. The disposable cartridge has least onesample chamber disposed in fluid communication with at least one assaychamber containing at least one assay chemical facilitating thedetection of the select attribute. The food assay system comprises, afluid collection carrier configured to: (i) hold the absorptive media incontact with the fluid sample during collection, (ii) carry theabsorptive media into the disposable assay cartridge for assaying thefluid sample, and (iii) produce a fluid-retaining barrier with thedisposable assay cartridge while assaying the fluid sample. The fluidcollection carrier is configured to be placed into the sample chambersuch that the assay chemical is disposed in combination with the fluidsample to determine whether the select attribute is present.

In yet another embodiment, a method for collecting a blood sample isprovided comprising the steps of: providing a cartridge having amedia-retaining end and a plunger/lancet assembly, loading themedia-retaining end with an absorptive media capable of absorbing aquantity of blood and placing the absorptive media of the assembly intocontact with the skin of a patient. The method further comprises thesteps of: activating the plunger/lancet assembly to cause a lancetthereof to penetrate the skin to effect collection of the quantity ofblood into the absorptive media, and placing the assembly and theblood-filled, absorptive media into a blood assaying device.

In yet another embodiment, a method is provided for preparing adiagnostic fluid sample for use with a fluid assay system. The methodcomprises the steps of: amplifying the fluid sample to increase thenumber of cells being tested, drawing a first volume of the fluid sampleinto a first syringe of a dual-barrel syringe and dispensing the firstvolume of the fluid sample through a media filter. The method furthercomprises the steps of: placing the media filter into a lysis module,dispensing a first portion of a lysis buffer into the lysis module fromthe second syringe of the dual-barrel syringe, and dispensing a secondportion of the lysis buffer through the media filter into a disposablecartridge of a fluid assay system.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is disclosed with reference to the accompanyingdrawings, wherein:

FIG. 1 is a perspective view of a portable diagnostic assay systemoperative to accept one of a plurality of disposable cartridgesconfigured to test fluid samples of collected blood or food samples.

FIG. 2 is an exploded perspective view of one of the disposablecartridges configured to test the biological samples.

FIG. 3 is a top view of the one of the disposable cartridgesillustrating a variety of assay chambers including a central assaychamber, one of which contains an assay chemical suitable to breakdownthe fluid sample to detect a particular blood attribute.

FIG. 4 is a bottom view of the disposable cartridge shown in FIG. 3illustrating a variety of channels operative to move at least a portionof the fluid sample from one chamber to another the purpose ofperforming multiple operations on the fluid sample.

FIGS. 5 and 6 are perspective and profile views, respectively, of anovel blood collection assembly according to one embodiment of thedisclosure including: a cartridge body, a blood-collection endconfigured to secure an absorptive media, and a trigger operative toactivate the extension and retraction of a lancet disposed within acavity of the assembly body and projecting through an aperture in theabsorptive media to effect the collection of a blood sample.

FIG. 7 is an exploded view of the blood collection assembly including anupper body including a pair of laterally projecting finger-flanges, alower body including a blood-retention end, a trigger portion, a pistonportion, an absorptive media and a coil spring.

FIG. 8 depicts the blood collection assembly being placed into adisposable cartridge of a portable diagnostic assay system.

FIG. 9 depicts the blood collection assembly seated in the disposablecartridge of the portable diagnostic assay system.

FIG. 10 depicts an isolated perspective view of the trigger and pistonportions of the plunger each having a plurality of mating teeth and atelescopic mounting surface for permitting relative motion between thetrigger and piston portions.

FIG. 11 depicts the cavity of the upper and lower body portions formounting the plunger and absorptive media of the blood collectionassembly.

FIG. 12 depicts an enlarged internal view of the cavity depicting guideand retention surfaces for axial translation of the plunger,auto-retraction of the piston portion, and a locking feature of thetrigger portion in a depressed or retracted position.

FIG. 13 depicts a novel fluid collection device including an absorptivemedia disposed at the tip end of a carrier configured to: (i) hold theabsorptive media in contact with the fluid sample during collection,(ii) carry the absorptive media into a portable fluid assaying system,and (iii) produce a fluid-tight or fluid-retaining seal/barrier with theportable fluid assaying system while performing an analysis of the fluidsample.

FIG. 13a depicts an alternate embodiment of the carrier including a plugfunctionally replacing a cap to produce the fluid-tight orfluid-retaining seal barrier with the portable fluid assaying system.

FIG. 14 depicts the fluid collection device being placed into, andseated within, a disposable cartridge of a portable diagnostic assaysystem.

FIG. 15 depicts a perspective view of a dual-barrel syringe facilitatingthe preparation of a diagnostic fluid sample, including a first syringeoperative to draw a quantity of the fluid sample, a second syringejuxtaposed with and sharing a common wall with the first syringe, thesecond syringe containing a lysis buffer, and a valve mechanismcontaining a nozzle which may be rotated into fluid communication withan opening in each barrel of the first and second syringe.

FIGS. 16-19 depict the dual-barrel syringe in various operatingpositions including drawing, dispensing, exposing and rinsing/flushingthe fluid sample in preparation for assay testing within a portablebiological assay system.

Corresponding reference characters indicate corresponding partsthroughout the several views. The examples set out herein illustrateseveral embodiments of the invention but should not be construed aslimiting the scope of the invention in any manner.

DETAILED DESCRIPTION

A blood collection assembly is described for use in combination with aportable/automated assay system such as that described incommonly-owned, co-pending U.S. patent application Ser. No. 15/157,584filed May 18, 2016 entitled “Method and System for Sample Preparation”which is hereby included by reference in its entirety. The bloodcollection assembly may be used in combination with a variety of blooddiagnostic cartridges which may be used to detect any of a variety ofdiseases which may be found in a blood specimen. For example, such blooddiagnostic cartridges may be dedicated cartridges useful for detectingHepatitis, Autoimmune Deficiency Syndrome (AIDS/HIV), Diabetes,Leukemia, Graves, Lupus, Multiple Myeloma, etc., just naming a smallfraction of the various blood borne diseases that the portable/automatedassay system may be configured to detect.

More specifically, and referring to FIGS. 1 and 2, the system employsthe use of a portable assay system 10 which receives any one of avariety of disposable assay cartridges 20, each selectively configuredfor detecting a particular attribute of a fluid sample. The portableassay system 10 includes one or more linear and rotary actuatorsoperative to move fluids into, and out of, various compartments orchambers of the disposable assay cartridge 20 for the purpose ofidentifying or detecting a fluid attribute. More specifically, a signalprocessor 14, i.e., a PC board, controls a rotary actuator (not shown)of the portable assay system 10 so as to align one of a variety of ports16, disposed about a cylindrical rotor 18, with a syringe barrel 22 ofthe assay cartridge 20. Furthermore, the processor 14 controls a LinearVariable Displacement Transducer (LVDT) 24, to displace a shaft 26 forthe purpose of developing pressure i.e., positive or negative (vacuum)in the syringe barrel 22. That is, the shaft 26 displaces a plunger 28within the syringe 22 to move and or admix fluids contained in one ormore of the chambers 30, 32.

The disposable cartridge 20 provides an automated process for preparingthe fluid sample for analysis and/or performing the fluid sampleanalysis. The sample preparation process allows for disruption of cells,sizing of DNA and RNA, and concentration/clean-up of the material foranalysis. More specifically, the sample preparation process of theinstant disclosure prepares fragments of DNA and RNA in a size range ofbetween about 100 and 10,000 base pairs. The chambers can be used todeliver the reagents necessary for end-repair and kinase treatment.Enzymes may be stored dry and rehydrated in the disposable cartridge, oradded to the disposable cartridge, just prior to use. The use of arotary design allows for a single plunger to draw and dispense fluidsamples without the need for a complex system of valves to open andclose at various times. This greatly reduces potential for leaks andfailure of the device compared to conventional systems. It will also beappreciated that the system greatly diminishes the potential for humanerror.

In FIGS. 3 and 4, the cylindrical rotor 18 includes a central chamber 30and a plurality of assay chambers 32, 34 surrounded, and separated by,one or more radial or circumferential walls 36. In the describedembodiment, the central chamber 30 receives the fluid sample while thesurrounding chambers 32, 34 may contain a premeasured assay chemical orreagent for the purpose of detecting an attribute of the fluid sample.The chemical or reagents may be initially dry and rehydrated immediatelyprior to conducting a test. Some of the chambers 32, 34 may be open toallow the introduction of an assay chemical while an assay procedure isunderway or in process. The chambers 30, 32, 34 are disposed in fluidcommunication, e.g., from one of the ports 16 to one of the chambers 30,32, 34, by channels 40, 42 molded in an underside surface 42 of therotor 18. For example, a port 16, corresponding to aperture 42, may bein fluid communication with the central chamber 30, via aperture 50.

Blood Collection Assembly

In FIGS. 5-8, an embodiment of a novel blood collection assembly 100comprises: (i) a body 104 having a blood-sampling end 106 configured tohold an absorptive media or filter 108, (ii) a lancet 112 disposedwithin a cavity 116 (See FIG. 7) of the body 104 and having a lance 118at one end thereof, and (iii) a plunger or plunger assembly 120configured to extend and retract the lancet 112 through the absorptivemedia or filter 108 to lance a dermal membrane, (i.e., the skin of apatient), and collect a blood sample within the absorptive media orfilter 108. Once a blood sample has been collected, the assembly body104 containing the blood-filled, absorptive media or filter 108 isconfigured to be placed into a blood assay device 10, i.e., the fluidsample chamber 30 of the disposable cartridge 20. This step may beperformed immediately, or involve the sterile packaging/storing and/ortransport of the blood sample, for subsequent analysis. Notwithstandingthe time between collection and analysis, the blood collection assembly100 is configured to be placed into a blood assay device 10 to elute theblood from the absorptive media 108. Furthermore, the blood collectionassembly closes the sample chamber, i.e., produces a fluid-tight seal orfluid barrier, such that fluids may flow between ports 16 as pressure isdeveloped in the various chambers 30, 32, 34 and channels 40, 42 of thedisposable cartridge 20.

In the described embodiment, the assembly body 104 includes an upperbody portion 104 a and a lower body portion 104 b which collectivelydefine the cavity 116. The body 104 is split to allow assembly of theplunger or plunger assembly 120 for insertion into the cavity 116, or tofacilitate the replacement/removal of the absorptive media 108. Whilethe absorptive media 108 may be replaced following use, the bloodcollection assembly of the present disclosure is intended to bedisposable, similar to the disposable cartridge that it supplies.

The upper body portion 104 a includes a pair of finger-receiving flanges136, 138 projecting laterally from the assembly body 104 to facilitatehandling of the assembly 100 while placing the absorptive media 108against the dermal membrane or skin The lower body portion 104 b isconfigured to secure the absorptive media 108 within an annular grooveor recess formed at the tip-end of the lower body portion 104 b, i.e.,at the tip of the blood-sampling end 106 of the assembly body 104.

The lancet 112 comprises a conventional tubular shaft having an endwhich is cut at a shallow angle, i.e., inclined, to produce a pointedtip end 118. The tip may be machined at an angle to produce a piercingtip, or sharpened to produce a razor-sharp lance 118. One end of thelancet 112 is embedded within a piston portion of the plunger or plungerassembly 120, discussed in greater detail below, while the other end ofthe lancet 112 faces the absorptive media 108 while disposed within thecavity 116 of the blood collection assembly 100.

The absorptive media 108 may be any material that absorbs and retains aliquid sample (paper, cellulose matrix, etc.) The material can be cut,pleated or woven in any manner to adjust the collected volume. In oneembodiment, the absorptive media 108 includes a cellulose fiber filterhaving cotton linters treated to achieve an alpha cellulose contentgreater than about ninety-eight percent (98%). Filter materials suitablefor use include Whatman Brand filters such as the Whatman FTA Eluteseries of paper products which facilitates: (i) long-term roomtemperature DNA preservation, (ii) multiple amplifications from a singlesample, and (iii) ease of elution.

In the described embodiment, the absorptive media 108 is an annular ringhaving an aperture 142 for receiving the lancet 112 upon activation ofthe plunger 120. While an annular ring is described, the absorptivemedia may have any shape provided it allows the lancet to penetrate orpass through a portion of the media material.

In one embodiment, the plunger 120 is spring-biased within the cavity116 of the assembly body 104 to be retracted and extended relative tothe assembly body 104. Furthermore, since the lancet 112 is connected tothe plunger 120, the lancet 112 may also extend and retract within thecavity 116 to urge the lance 118 through the opening or aperture 142 inthe absorptive media 108. In the described embodiment, a coil spring 160abuts a raised ring-shaped shoulder 162 formed along the outercircumference of the trigger 120, allowing the trigger 120 to bedepressed from, and returned to, an extended position. As mentioned inthe preceding sentence, inasmuch as the lancet 112 is mounted to thetrigger 120, the lancing end 118 may also extend and retract through theopening 142 in the absorptive media 108.

In FIGS. 10-12, the plunger or plunger assembly 120 includes a pistonportion 122 and a trigger portion 124. The piston portion 122 (i)defines a first cylindrical surface 126 slidably guided along aninternal cylindrical bore or surface 144 of the cavity 116, (ii) definesa second cylindrical surface 128 telescopically mounting within a bore134 of the trigger portion 124, and (iii) includes a pair ofarrow-shaped radial protrusions 154 (FIG. 10) to axially guide thepiston portion 122 within axial channels 156, while preventing rotationof the piston portion 122 about an elongate axis 100A (FIG. 11) of theassembly 100. The trigger portion 124 is: (i) disposed between thefinger-receiving flanges 136, 138 of the upper body portion 104 a of theassembly 100, (ii) slideably guided within a bore 135 in the upper bodyportion 104 a, and (iii) axially guided within the bore 142 (see FIG.12) by the raised linear guide 156 within the cavity 116.

The piston and trigger portions 122, 124 include first and secondcrown-shaped teeth 164, 166, respectively, which facilitate the transferof axial motion between the piston and trigger portions 122, 124 whileimparting rotational motion as a consequence of engagement between theinclined surfaces of the crown-shaped teeth 164, 166. Inasmuch as thepiston portion 122 employs anti-rotation protrusions 154, the pistonportion travels axially within the guide 156 while the trigger portion124 rotates into a shoulder notch 170. The trigger portion 124 onlymoves into the notch 170 as the trigger portion 124 moves axially pastnotch 170 or as the trigger portion 124 moves past a threshold axiallocation.

The relative rotation between the piston and trigger portions 122, 124causes the piston portion 122 to recede into the trigger portion 124 asa consequence of the telescopic mount between the piston and triggerportions portion 122, 124. Furthermore, inasmuch as the lancet 112 isseated within the piston portion 124, the lancet 112 “auto-retracts”when the trigger portion 124 rotates under the notch 170. Furthermore,when the trigger portion 124 rotates beneath the notch 170, it is nolonger capable of retraction and extension. Accordingly, the triggerpiston 124 is “locked” and incapable of a second use. This feature maybe desirable to prevent cross-contamination of the blood sample.Alternatively, the lancet 122 may move into a position where it islocked by a housing shoulder to prevent the lancet 112 and the bloodcollection assembly 100 from being used a second time.

Once a blood sample has been taken, the blood collection assembly 100 isplaced within the sample chamber 30 of the disposable cartridge 20. Theblood collection assembly 100 may include a sealing ring (not shown) atthe tip end of the assembly to facilitate the formation of a fluid-tightseal. Additionally, to augment release and elution of the blood from theabsorptive media 108, one or more apertures 172 (see FIG. 6) may beformed in the body 104 to facilitate fluid flow through the absorptivemedia 108.

Fluid Sample Carrier

In FIGS. 13, 13 a, and 14, a novel food assay system and fluid samplecarrier 200 includes an absorptive media 208 configured to collect andrelease or elute a fluid sample when disposed in combination with adisposable cartridge 20 of a food assay system 10. The disposable assaycartridge 20 is essentially the same as was previously described, i.e.,the arrangement of chambers, channels, ports, and plungers etc. Theprincipal difference between the disposable assay cartridges 20 relatesto the types of biological agents or attributes being assayed. Forexample, a cartridge 20 may be configured to assay for salmonella, E.coli, mad-cows disease, and other food borne pathogens. Additionally,the assembly can be configured to assay West Nile Virus or Lime Disease.

The fluid collection carrier 200 of this embodiment, includes a samplecollection end 202, a protective handle 204, and a connecting shaft 206disposed therebetween. The sample collection end 202 includes a media ormedia filter 220 suitable for absorbing and carrying fluids which aresuspected of containing a hazardous or dangerous pathogen.

The absorptive media 208 may be any material that absorbs and retains aliquid sample (paper, cellulose matrix, etc.). In one embodiment, theabsorptive media 208 includes a cellulose fiber having cotton linterstreated to achieve an alpha cellulose content greater than aboutninety-eight percent (98%). Fiber media materials suitable for useinclude Whatman Brand filters such as the Whatman FTA Elute series ofpaper products which facilitates long-term room temperature preservationand ease of elution.

In the described embodiment, the absorptive media 208 will have anelliptical shape and be sized to collect a select volume of fluid. Whilean ellipse is depicted, the absorptive media 208 may have any shapesuitable for swabbing a surface or absorbing a standing fluid.

In one embodiment, the carrier 200 comprises a sealing member or cap 210disposed between the shaft 206 and the protective handle 204. The cap210 is configured to be disposed over a rim 216 (FIG. 14) of the samplechamber 30 of the disposable cartridge 20 and form a fluid-tight orfluid-retaining seal or barrier between it and the disposable cartridge20. In the described embodiment, the cap 210 defines a cavity 218 toaccept the rim 216 of the disposable cartridge 20. Similar to thepreviously-described blood collection assembly 100, the carrier 200forms a seal or barrier with the sample chamber 30 such that theabsorptive media 208 may elute the fluid to assay for food-bornediseases, hazardous biological agents, and/or dangerous pathogens.

In another embodiment depicted in FIG. 13 a, an elastomer plug 220functionally replaces the cap 210 to produce the seal or barrier withthe sample chamber 30. In this embodiment, the plug 220 is receivedwithin the sample chamber 30 and forms a seal with the internalperiphery of the sample chamber 30.

In another embodiment, the sealing member 210, 220 forms a fluid-tightseal with a vial 230 configured to maintain the purity or sterility ofthe fluid sample, both before and after collection. Furthermore, thevial 230 may be filled with a sterile fluid before and/or after samplecollection.

The fluid collection carrier 200 is configured to: (i) hold theabsorptive media 208 in contact with the fluid sample so as to cause theabsorptive media 208 to collect a quantity of the fluid sample; (ii)carry the absorptive media 208 into the disposable assay cartridge 20,and (iii) close an end of the sample chamber 30 to prevent the egress ofassay fluids and/or assay chemicals during assay testing.

In the described embodiment, the protective handle 204 includes a flange212 projecting laterally outboard from an axis 206A defined by the shaft206. The flange 212 is disposed axially aft, or rearward of, the sealingmember 210 and functions to protect a handler from exposure to thefood-borne diseases, hazardous biological agents, and/or dangerouspathogens carried within the absorptive media 208.

Dual-Barrel Syringe for Preparation of a Food Sample

Many diagnostic tests, particularly food safety testing, requirebacterial growth or amplification of the sample, prior to testing. Thisis due to the fact that certain agents, particularly those in food,often present very low levels of the biological attribute sought to betested or detected in a sample. To enhance the probability of detectingthe biological attribute, i.e., a test sample with a low Colony FormingUnit (CFU) count, a large sample size, i.e., typically more than tenmilliliters (10 ml) can be required. This requirement, however, runscounter to many diagnostic assay systems which are designed for muchsmaller sample inputs, i.e., typically less than about fiftymicro-liters (50 μl.)

To integrate these competing requirements, a multi-barrel syringe 300 incombination with a selector valve 304 may be employed to draw, dispense,expose, and rinse/flush the fluid sample from an initial quantity of afood sample which has been amplified immediately prior to conducting anassay test.

More specifically, and referring to FIGS. 15 and 16, the syringe 300comprises first and second barrels 308, 312 having first and secondsyringe plungers 318, 322, and a selector valve 326 rotatably mounted toan end of the syringe 300 about an axis of rotation 304A and having asyringe nozzle 330. The first and second barrels 308, 312 arejuxtaposed, share a common wall 332, and define first and secondapertures 338, 342 at an end of each of the first and second barrels308, 312, respectively.

The first barrel 308 of the dual-barrel syringe 300 is larger than thesecond barrel 312, and in the described embodiment, the volume of thefirst barrel 308 is between about five (5) to one-hundred (100) timeslarger than the volume of the second barrel 312. Furthermore, the firstbarrel 308 of the dual-barrel syringe 300 is initially empty to allowthe first barrel 308 to draw a fluid sample from a biological sample 350(FIG. 16) which has been amplified/colonized to increase the CFUconcentration. The second barrel 312 of the dual-barrel syringe 300 isinitially filled with a lysis buffer which is useful for breaking-downthe assay sample. In the described embodiment, the second barrel 312 maycontain approximately three hundred micro-liters (300 μl) of a lysisbuffer.

The method for preparing the fluid sample for subsequent use in aportable assay sample system will be described in greater detail hereinbelow. Suffice to say at this juncture that, of the various componentsprovided as part of an aggregate kit, i.e., a kit for identifying aparticular attribute of a fluid/food sample, a dual-barrel syringe 300will be provided wherein: (i) the first barrel 308 is significantlylarger in volume than the second barrel 312, (ii) the first barrel 308is initially empty to allow it to be used for drawing and dispensing anassay sample through a lysis filter, and (iii) the second barrel 312 iscompletely filled with a lysis buffer and dispensed in stages toproperly prepare the assay sample.

Returning to FIG. 16, a first step of the preparation method involvespreparing the biological food sample 350 in a conventional manner suchthat the biological food sample 350 is amplified/colonized to increaseits Colony Forming Unit (CFU) count or concentration. In a second step,the plunger 318 of the first barrel is depressed to its bottom positionand the selection valve 304 is rotated to align the aperture 338 of thefirst barrel 308 with the nozzle passageway of the selector valve 304.The nozzle 330 of the selector value 304 is then placed in theprepared/pre-treated food sample 350, and the plunger 318 is raised todraw the fluid/food sample into the first barrel 308.

In FIG. 17, a third, or subsequent step, involves depressing the plunger318 of the first barrel 308 to dispense the entire contents/volume ofthe first barrel 308 through a lysis filter 354 within a lysis module360. The filter media 354 contains a filter material of appropriateporosity to extract the bacterial content of the fluid/food sample withhigh efficiency. Once all of the assay sample has been captured by thelysis filter 354, the selector valve 304 is rotated from the aperture338 associated with the first barrel 308 to the aperture 342 associatedwith the second barrel 312.

In FIG. 18, a fourth step involves dispensing a portion of the lysisbuffer from second barrel 312 into the lysis module 360. In thedescribed embodiment, about one-half of the lysis buffer is dispensed inthe lysis module 360. Further, the lysis module 360 is closed in thisstep to allow the module 360 to hold the contents of the syringe 300,i.e., the lysis buffer, for a predetermined minimum period of time. Inthe described embodiment, the filtered contents of the lysis filter 354are exposed into the lysis buffer for a period of at least five minutes(5 mins.), and preferably for as much as fifteen minutes (15 mins.) Thelysis buffer breaks-down and liberates the nucleic acids within thelysed material for subsequent analysis. In certain embodiments, the timeperiod of exposure may be automated such that the timing is controlledby computer software. In yet other embodiments, the lysis module 360 maybe heated to facilitate and accelerate the lysis reactions.

In FIG. 19, a fifth, and final, step involves flushing/rinsing theremaining portion of the lysis buffer, i.e., the remaining one-hundredand fifty micro-liters (150 μl,) through the lysis module 360 into thesample chamber 30 of the disposable cartridge 20. In other embodiments,the fluid/food sample could be purged into any suitable sample containerbased on the subsequent analysis to be provided/envisioned.

As mentioned above, this method allows for the detection of sampleshaving a low CFU concentration in a sample by providing higherconcentrations depending on the relative size of the syringe 300 and thelysis module 360. This method has the added benefit of extracting therelevant sample from the high salt broths often used in cultured foodsamples which have, in the past, been problematic for DNA purificationand subsequent Polymerase Chain Reactions (PCRs.)

EXAMPLE

In one example, a particular attribute of a food/fluid sample was to bedetected based on a desired Colony Forming Unit (CFU)/ml. A tenmilliliter (10 ml) sample was extracted from a broth produced by growingbacteria from a twenty-five gram (25 g) sample of ground beef. Theselector valve 304 is switched to flow the 10 ml sample through a onehundred and fifty micro-liter (150 μl) lysis module 360 containing afilter medium 354 to extract the bacterial content in the sample. Afterextraction, one hundred and fifty micro-liters (150 μl) of a lysisbuffer was injected into the to the lysis module 360 and allowed toreact for approximately 5 minutes. After the prescribed time period,another one hundred and fifty micro-liters (150 μl) of the lysis bufferis dispensed through the filter medium 354 to cause the entire 300micro-liters (300 μl) to be flushed into the sample chamber 30 of thedisposable cartridge 20. The lysed DNA material is then flushed throughinto an assay cartridge

While the invention has been described with reference to particularembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from thescope of the invention.

Therefore, it is intended that the invention not be limited to theparticular embodiments disclosed as the best mode contemplated forcarrying out this invention, but that the invention will include allembodiments falling within the scope and spirit of the appended claims.

1. A blood assay system for the assaying a blood sample, comprising: anabsorptive media configured to collect and release the blood sample; ablood collection assembly defining a cavity and a blood-sampling endconfigured to hold the absorptive media against a dermal membranecontaining the blood sample; a lancet disposed within the cavity andhaving a lance at one end thereof; a plunger configured to extend andretract the lancet through the absorptive media to lance the dermalmembrane and collect the blood sample within the absorptive media; and adisposable assay cartridge configured to assay the blood sample fordetecting the presence of a particular attribute, the disposablecartridge having at least one sample chamber disposed in fluidcommunication with at least one other assay chamber and containing atleast one assay chemical operative to detect the particular attribute;wherein the blood collection assembly is configured to be placed intoand sealed against the at least one sample chamber to elute the bloodsample from the blood collection assembly and combine the eluted bloodwith the at least one assay chemical to detect for the presence of theattribute.
 2. The blood assay system of claim 1 wherein the absorptivemedia is a cellulose fiber filter comprising cotton linters which havebeen treated to achieve an alpha cellulose content greater thanninety-eight (98%.)
 3. The blood assay system of claim 1 wherein theabsorptive media includes an aperture facilitating the passage of thelance upon activation of the plunger.
 4. The blood assay system of claim1 wherein the assembly includes at least one aperture through a wall ofthe assembly into the cavity to facilitate elution of the blood samplefrom the absorptive media.
 5. The blood assay system of claim 1 whereinthe plunger includes a finger-receiving flanges projecting laterallyfrom the assembly to hold the absorptive media against the dermalmembrane.
 6. The blood assay system of claim 1 wherein the plungerincludes: (i) a piston portion defining a first surface slidably guidedalong and internal wall of the cavity, defining a second surfacecoaxially aligned with first surface, and (ii) a trigger portiondisposed through an aperture of the assembly and having an internal boretelescopically mounting to the second surface of the piston portion, thetrigger portion projecting outwardly of the cavity to an extendedposition in response to spring-biasing of the piston portion of theplunger; and wherein the lancet mounts to the piston portion to lancethe dermal membrane when the trigger portion is depressed.
 7. The bloodassay system of claim 6 wherein the lancet retracts automatically withinthe cavity in response to axial displacement of the trigger portionrelative to the piston portion of the plunger.
 8. The blood assay systemof claim 7 wherein the plunger includes a coil spring disposed betweenthe blood sampling end of the assembly and the piston portion of theplunger.
 9. The blood assay system of claim 8 wherein the triggerportion telescopes relative to the piston portion such that the triggerportion remains depressed following retraction of the lancet.
 10. Ablood collection assembly facilitating the assay of a blood sample,comprising: an absorptive media configured to collect and release theblood sample; a body defining a cavity and a blood-sampling endconfigured to hold the absorptive media against a blood-containingmembrane; a lancet disposed within the cavity and having a lance at oneend thereof; a plunger configured to extend and retract the lancetthrough the absorptive media to lance the membrane and collect the bloodsample within the absorptive media; and wherein the body containing theabsorptive media is configured to be placed into and sealed against achamber of a blood assay device for extraction of the blood sample fromthe absorptive media.
 11. The blood collection assembly of claim 10wherein the absorptive media is a cellulose fiber filter comprisingcotton linters which have been treated to achieve an alpha cellulosecontent greater than ninety-eight (98%.)
 12. The blood collectionassembly of claim 10 wherein the absorptive media includes an aperturefacilitating the passage of the lance upon activation of the plunger.13. The blood collection assembly of claim 10 wherein the plungerincludes a finger-receiving flanges projecting laterally from theassembly to hold the absorptive media against the membrane.
 14. Theblood collection assembly of claim 10 wherein the plunger includes: (i)a piston portion defining a first surface slidably guided along andinternal wall of the cavity, defining a second surface coaxially alignedwith first surface, and (ii) a trigger portion disposed through anaperture of the assembly and having an internal bore telescopicallymounting to the second surface of the piston portion, the triggerportion projecting outwardly of the cavity to an extended position inresponse to spring-biasing of the piston portion of the plunger; andwherein the lancet mounts to the piston portion and lances the a dermalmembrane when the trigger portion is retracted from the extendedposition to a depressed position.
 15. The blood collection assembly ofclaim 14 wherein the lancet retracts automatically within the cavity inresponse to axial displacement of the trigger portion relative to thepiston portion of the plunger.
 16. The blood collection assembly ofclaim 14 wherein the plunger includes a coil spring disposed between theblood sampling end of the assembly and the piston portion of theplunger.
 17. The blood collection assembly of claim 14 wherein thetrigger portion telescopes relative to the piston portion such that thetrigger portion remains depressed following retraction of the lancet.18. A method of collecting a blood sample, comprising the steps of:providing a blood collection assembly having a media-retaining end and aplunger/lancet assembly; loading the media-retaining end with anabsorptive media capable of absorbing a quantity of blood; placing theabsorptive media of the assembly into contact with the skin of apatient, activating the plunger/lancet assembly to cause a lancetthereof to penetrate the skin to effect collection of the quantity ofblood into the absorptive media; and placing the blood collectionassembly and the absorptive media into a blood assaying device andsealing the blood collection assembly against a chamber of the bloodassaying device.
 19. The method of claim 18 further comprising the stepof: automatically retracting the lancet into cavity when a plunger isactivated.
 20. The method of claim 18 further comprising the step of:inhibiting a second activation of the lancet by the plunger/lancetassembly following an initial activation by the plunger/lancet assembly.21. A blood collection assembly for obtaining and testing blood samplesfrom a patient, comprising: an assembly body having an upper bodyportion defining a plunger end and a pair of finger-receiving flangesprojecting outwardly of the upper body portion, a lower body portiondefining a blood-sampling end and an opening, and a cavity defining acylindrical bore defined by the upper and lower body portions; a plungerdisposed between the finger-receiving flanges and capable of axialdisplacement relative to the assembly, the plunger having: (i) a pistonportion defining a first cylindrical surface slidably guided along thecylindrical bore of the cavity and defining a second cylindrical surfacecoaxially aligned with cylindrical bore of the cavity, and (ii) atrigger portion slideably guided by an aperture in the upper bodyportion of the assembly and having an internal bore telescopicallymounting over the second cylindrical surface of the piston portion, thetrigger and piston portions being spring-biased from a depressedposition to a retracted position, an absorptive media disposed withinthe opening; a lancet disposed within the cavity of the assembly, havingone end affixed to the piston portion of the plunger and another enddefining a skin-penetrating lance facing the media-retaining opening ofthe absorptive media; wherein, the blood collection assembly is placedagainst a dermal membrane to collect a sample of blood by activation ofthe lancet and absorption of a sample of blood by the absorptive mediaand is placed into a blood sampling device for elution and testing ofthe blood sample from the absorptive media.
 22. The blood collectionassembly of claim 21 wherein the absorptive media is a cellulose fiberfilter comprising cotton linters which have been treated to achieve analpha cellulose content greater than ninety-eight (98%.)
 23. The bloodcollection assembly of claim 21 wherein the absorptive media includes anaperture facilitating the passage of the skin-penetrating lance uponactivation of the plunger.